JPH04335251A - Optical disk device - Google Patents

Abstract

PURPOSE:To detect the inclination of a disk without rotating it by providing two sets of sensors lined in the radial direction and the circumferential direction of a disk respectively to hold a light source between them and providing a circuit for detecting whether a sensor output difference of each set of the two sets falls within a prescribed range or not. CONSTITUTION:The disk 1 is set on a spindle motor 2, and recorded data of the disk 1 is read out by a head 4 in moving a carriage 3. In this case, four sensors 6a-6d are provided in a cross form with a center of the light source 6e, where the sensors 6a and 6b are lined in the radial direction of the disk 1, while the sensors 6a and 6b in the circumferential direction. When the disk 1 is not horizontal, a difference of the sensors 6a and 6b or 6c and 6d is generated in detecting light K, and this is detected by the detecting circuit, so that the inclination can be detected. By this method, the disk 1 can be detected in inclination in various directions.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc device, and more particularly, to an optical disc device that can detect the tilt of an optical disc when it is set in the device.

0002

2. Description of the Related Art Generally, in an optical disk device, the optical disk is replaceable. For this reason, when setting a disk, due to variations in various setting operations, disturbances, etc., the disk may not be set correctly, and the disk may be set obliquely.

Conventional optical disc devices do not detect the inclination of the disc, so even if the disc is set diagonally, it cannot be detected and the loading operation continues.

0004

In conventional optical disc devices, there has been a problem in that when the optical disc is tilted at a large angle when the optical disc is set, the focus servo cannot be pulled in properly. When the tilt is small, focus pull-in is successful, but (it is possible to pull in the focus because it is done on the inner circumference of the disk).There is a problem that the focus servo may become disconnected when seeking to the outer circumference. Ta.

For this reason, there is a problem in that the true cause of the error, which is a disc setting error, is not known, and the cause is incorrectly detected as a focus servo error.

[0006] Conventional optical disc devices cannot detect whether or not the set disc is set correctly, so if it is not set correctly, it cannot be detected, and it may be detected incorrectly as if the focus servo was the cause. There was a problem with it being put away.

An object of the present invention is to provide an optical disc device that solves the above problems.

[0008]

[Means for Solving the Problems] An optical disc device of the present invention includes one or more light sources, two sensor sets arranged in the radial direction of the disc sandwiching the light source, and a circle of the disc sandwiching the light source. The device includes two sets of sensors arranged in the circumferential direction, and a detection circuit that detects when the output difference of the sensors in each of the two sets is out of a certain range.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the optical disc apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of an optical disc device according to an embodiment of the present invention. The disk 1 is set on the spindle motor 2 manually or by a loader mechanism. When the disk 1 is set, the carriage 3 is moved and the head 4 writes and reads data on the disk 1. The spindle motor 2 and the carriage 3 are placed on the vector 5 to maintain their positional relationship. In this embodiment, the tilt sensor 6 is connected to the carriage 3.
It is attached to the opposite side of head 4 (of course, the same effect can be obtained on the same side). FIG. 1(a) is a schematic diagram when the disc 1 is set diagonally, and FIG. 1(b) is a schematic diagram when the disc 1 is correctly set.

FIG. 2(a) is a schematic diagram of a tilt sensor 6 according to an embodiment of the present invention. Four sensors (6a, 6b, 6c, 6d) are attached in a cross shape around the LED 6e. FIG. 2(b) shows each sensor (6a, 6b, 6c, 6d)
FIG. 6 is a second schematic diagram of the tilt sensor 6 with LEDs (6f, 6g, 6h, 6i) for each of the tilt sensors. (The following explanation will be given assuming that the sensors 6a and 6b are arranged in the radial direction).

FIG. 3 is a schematic diagram showing the function of the tilt sensor 6 according to the embodiment of the present invention.

FIG. 4 shows a detection circuit that generates a signal from the output of the tilt sensor 6 to detect that the disk 1 is tilted. The operational amplifiers (7, 8) each have a sensor group (6
a, 6b and 6c, 6d), and comparator (9
, 10, 11, 12) outputs an output when the output of the operational amplifier (7, 8) exceeds a certain range, and the OR circuit 13
Create an OR of the outputs of the comparators (9, 10, 11, 12).

Next, the operation will be explained with reference to FIG. In FIG. 3(b), when the disk 1 is correctly set, the sensor surface of the tilt sensor 6 and the disk 1 become horizontal. Therefore, the detection light K emitted from the LED 6e is
Since it hits perpendicular to , it returns straight to LED6e. Even if there is diffuse reflection on the surface of the disk 1, there is no significant difference in the light entering the sensors 6a and 6b. However, in Fig. 3(a), if disk 1 is set diagonally, L
The detection light K output from the ED 6e is tilted by the disk 1 in the direction of the sensor 6b (if tilted in the opposite direction, the detection light K is tilted toward the sensor 6a).
side). Therefore, by looking at the difference in the outputs of the sensors 6a and 6b, it can be determined whether the disk 1 is tilted or not.

FIG. 4 shows an embodiment of a circuit for checking the output of a sensor. The difference between the sensors 6a and 6b is created by an operational amplifier 7, the output of which is compared in a comparator 9 with V1 and in a comparator 10 with V2. (V1 and V2 are determined in advance). When the output of the operational amplifier 7 is larger than V1, the output of the comparator 9 becomes HIGH, and when it is smaller than V2, the output of the comparator 10 becomes HIGH. Therefore, if the outputs of comparator 9 and comparator 10 are ORed, sensors 6a and 6b
It is possible to detect that the difference has exceeded a certain range, that is, that the inclination of the disk 1 has become large.

In this embodiment, sensors 6c and 6d are installed and an output circuit is also provided so that the inclination of the sensors 6a and 6b in the perpendicular direction (circumferential direction) can be detected at the same time. This is because when detecting in two directions, even if the disk 1 is tilted in a plane perpendicular to the paper plane of FIG. 1, the tilt can be detected even if the disk 1 is not rotated.

[0016] This is because if the disk 1 is rotated and then detected, the inclination of the disk 1 can be detected using only the pair of sensors 6a and 6b. This is to avoid this.

[0017]

As explained above, the present invention has the effect that by attaching a tilt sensor, it is possible to detect that a disk is set at an angle. Furthermore, by having two sets of sensors, one in the radial direction and the other in the circumferential direction, it is possible to detect the inclination of the disk in various directions without rotating the disk.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an overview of an optical disc device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of the tilt sensor shown in the practical example of FIG. 1;

FIG. 3 is a schematic diagram illustrating the operation of the tilt sensor shown in FIG. 2;

FIG. 4 is a circuit diagram of a detection circuit that detects the inclination of a disk.

[Explanation of symbols]

1 Disc 6 Tilt sensor

Claims (1)

[Claims] Claim 1: An optical disc device capable of setting and resetting a disc, comprising one or more light sources,
Two sensor sets sandwiching the light source and lined up in the radial direction of the disk, two sensor sets sandwiching the light source and lined up in the circumferential direction of the disk, and a sensor output difference within the sensor set is set to a predetermined value. 1. An optical disc device comprising: a detection circuit that detects a deviation from the range.